Latency and Ping Tests

Discussion in 'Hardware' started by listedguru, Sep 1, 2008.

  1. Can anyone recommend some good latency and ping tests to test out my connection here? I want to compare it to a relatives cable internet connection. Can I ping sites like yahoo, etc to compare results? How can I test for packet loss, etc? I'm on AT&T's Uverse VDSL connection and it seems 'stuck' at times..

    -Guru
     
  2. What does it mean if something keeps timing out over the first few hops when I run a tracert to an IP address? Is something wrong with my connection? My time (in ms) seems fine but I keep seeing these timeouts...

    -Guru
     
  3. It depends.

    It might be that the router concerned doesn't want to respond to the number of pings its getting (not a problem because it doesn't affect its routing).

    It might be that there is a bad link which is causing the timeouts which is a problem. If there is a bad link though you should be seeing variability in the ping times to the routers further along the path.
     
  4. I pretty much get the same numbers (ms) everytime I run the trace test - also I'm seeing the request timed out along the same hops everytime. Not sure if this is bad or not? I'm not seeing any of my ping times over 50ms (I guess thats good). I'm going to test these numbers against a relatives cable internet connection (I'm on AT&T's Uverse)...

    -Guru
     
  5. Your fine as long as the "time-outs" that you see come AFTER you reach the server address of your destination.

    Normally, you have very low numbers on your local network for the first 8-9 "hops" and then you head out on the Internet-Superhighway where you then will see several hops to your final destination ( perhaps in the 80's or 90s ).

    Any "time-outs" that you see AFTER that final destination of your trading/quote server are absolutely meaningless!
     
  6. dcvtss

    dcvtss

    usually firewalls not responding to ICMP
     
  7. guru- funny- came here asking the same question.

    Was having the standard slowness with Sterling this afternoon. I time out the first line as well, but never thought that was the issue.

    For you tech guys....I have linked trace test.

    No biggie? Or is there something I need to fix?
     
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  8. dcvtss

    dcvtss

    The first line is your firewall/router/gateway (I'm assuming you are a home user based on the comcast looking partial domain names of the routers in the trace) dropping the ICMP packets from your traceroute. It is normal expected behavior. There are a lot of hops but it is not necessarily indicitive of the route your actual traffic will take beacuse Comcast is undoubtedly setting ICMP traffic to a lower COS in its network which could account for the extra "bouncing around" before leaving their egress router. Comcast does deep packet inspection based QOS on their network whether they continue to deny it or not (I think they just admitted it though) so my recommendation is to encrypt your traffic (easy to do if you use TWS) lest it be mistakenly identified as something on their naughty list like Bittorrent or streaming video not purchased from them and throttled by them injecting TCP resets. You have to be careful drawing conclusions from traceroute in general as it can give some unexpected and not exactly accurate results depending on network design.
     
  9. JackR

    JackR

    Download PingPlotter. Look at the very bottom of the PingPlotter page for the freeware version:
    www.pingplotter.com

    PingPlotter will show you latency and packet loss. Packet loss results in the retransmission of the missed packet(s) by the Transmission Control Protocol (TCP part of TCP/IP). This retransmission slows your data down.

    The tricky part in looking at the PingPlotter display is to be aware that you'll probably see packet loss at intermediate routers and none (maybe) further towards your broker. That is because the data stream has been fixed by the router that detected the packet loss so it is sending a complete, properly ordered stream onward. If you see packet loss on the first link you definitely have problems. If on the last link, your broker does.

    Also bear in mind that the routers on the backbone are running at multi-gigabyte or faster rates so a 1% packet loss is corrected so fast you will not even be aware it happened as your datastream is probably running at a 1 to 10 megabyte rate. However, high packet loss is a problem and PingPlotter will show it.

    Jack
     
    #10     Sep 2, 2008